【摘要】 考虑与震级、震中距相关的傅里叶幅值谱衰减关系,根据地震动非平稳性及设定震级、震中距、场地条件对地震动影响的分析,建立多维非平稳地震动合成的方法。基于波动理论和快速δ-矩阵算法求出地震波不同波型在设定地壳介质模型中的频散曲线,用以计算体波和面波各频率成分的到时t,并引入特性因子Q来考虑随机相位移动,最终得出体波和面波不同波型在窄频带上到达地表附近处某点地震动的到时及相位变化,从而合成多维地震动平动分量时程。根据该合成方法获得的三维地震动平动分量具有非平稳性,并能为结构抗震分析提供满足工程实际的地震动加速度时程。更多还原

【Abstract】 Considering Fourier amplitude spectrum attenuation relationship related to earthquake magnitude and distance,according to the analysis of non-stationary of earthquake ground motion,effect of given magnitude,distance,and site conditions on ground motion stability,multi-dimensional non-stationary earthquake motion synthesis method has been built. Based on the wave theory and the fast δ-matrix algorithm,the dispersion function of different wave modes in the crustal model is deducted to calculate arrival time t of the frequency components of the body wave and the surface wave. Meanwhile,the characteristic factor Q is introduced to consider the stochastic phase shift. Finally,the arrival time and the phase change of the body wave and surface wave at a certain point in the narrow frequency band are obtained,and the time history of the multi-dimensional ground motion is obtain. Multi-dimensional vibration of the translational components obtained by the synthesis method is non-stationary,and imitate actual seismic acceleration for structural seismic analysis.更多还原